阅读说明：本技术 一种耐海洋微生物腐蚀的高熵合金及其制备方法和应用 (High-entropy alloy resistant to marine microbial corrosion and preparation method and application thereof ) 是由 赵颖 石芸竹 梁涛 刘玉芝 于 2019-11-27 设计创作，主要内容包括：本发明提供了一种耐海洋微生物腐蚀的高熵合金,所述耐海洋微生物腐蚀的高熵合金的化学通式为Al<Sub>0.1</Sub>CoCrFeNiCu<Sub>x</Sub>,其中,x为Cu的摩尔分数,0.3≤x≤0.5。该耐海洋微生物腐蚀的高熵合金既具有很强的耐腐蚀性,又具有突出的抗菌性能,能够有效抵御海洋微生物的腐蚀。本发明还提供了耐海洋微生物腐蚀的高熵合金的制备方法和应用。(The invention provides a marine microorganism corrosion resistant high-entropy alloy, and the chemical general formula of the marine microorganism corrosion resistant high-entropy alloy is Al 0.1 CoCrFeNiCu x Wherein x is the mole fraction of Cu, and x is more than or equal to 0.3 and less than or equal to 0.5. The high-entropy alloy resistant to marine microorganism corrosion has strong corrosion resistance and outstanding antibacterial performance, and can effectively resist marine microorganism corrosion. The invention also provides a preparation method and application of the high-entropy alloy resistant to marine microbial corrosion.)

1. The high-entropy alloy resistant to marine microbial corrosion is characterized in that the general chemical formula of the high-entropy alloy resistant to marine microbial corrosion is Al_0.1CoCrFeNiCu_xWherein x is the mole fraction of Cu, and x is more than or equal to 0.3 and less than or equal to 0.5.

2. A high entropy marine microbial corrosion resistant alloy according to claim 1, wherein the crystal structure of the marine microbial corrosion resistant high entropy alloy is a face centered cubic structure.

3. The marine microorganism corrosion resistant high entropy alloy of claim 1, wherein in the chemical formula, x is 0.45. ltoreq. x.ltoreq.0.5.

4. The marine microbial corrosion resistant high entropy alloy of claim 1, wherein the marine microbial corrosion resistant high entropy alloy has an antimicrobial rate of 90% or more.

5. The marine microbial corrosion resistant high entropy alloy of claim 1 wherein the purity of each of Al, Co, Cr, Fe, Ni and Cu in the marine microbial corrosion resistant high entropy alloy is greater than 99.9%.

6. A preparation method of a high-entropy alloy resistant to marine microbial corrosion is characterized by comprising the following steps:

(1) after surface pretreatment is carried out on metal elementary substance raw materials of Al, Co, Cr, Fe, Ni and Cu, adding the raw materials into smelting equipment according to the mole fraction ratio of 0.1:1:1:1: x, wherein x is more than or equal to 0.3 and less than or equal to 0.5;

(2) firstly melting the metal simple substance raw material into alloy liquid under inert atmosphere, cooling to obtain an alloy ingot, and turning the alloy ingot over for more than four times;

(3) and (3) repeating the step (2) at least twice, and after the metal simple substance raw material is uniformly smelted, forming by fixing a die to obtain the high-entropy alloy resistant to marine microbial corrosion.

7. The preparation method according to claim 6, wherein the elemental metal raw materials of Al, Co, Cr, Fe, Ni and Cu are sequentially stacked into the smelting device from small to large in melting point; the purities of the metal elementary substance raw materials of Al, Co, Cr, Fe, Ni and Cu are all more than 99.9%.

8. The method of claim 6, wherein the crystal structure of the high entropy alloy that is resistant to marine microbial corrosion is a face centered cubic structure.

9. The method of claim 6, wherein the melting apparatus is a non-consumable vacuum arc furnace; before the smelting equipment is used for smelting the high-entropy alloy resistant to marine microorganism corrosion, metal titanium is smelted to remove impurities in the smelting equipment.

10. Use of the high-entropy alloy resistant to marine microbial corrosion according to any one of claims 1-5 or the high-entropy alloy resistant to marine microbial corrosion prepared by the preparation method according to any one of claims 6-9 in marine engineering equipment.

Technical Field

The invention relates to the technical field of metal alloy materials, in particular to a marine microorganism corrosion resistant high-entropy alloy and a preparation method and application thereof.

Background

Marine corrosion is a significant problem facing marine engineering, and statistically, the annual marine corrosion loss is about $ 0.8 trillion, which accounts for 1/3 in the total amount of global corrosion ($ 2.4 trillion). At present, key structural parts of seawater pipelines, pump valves, heat exchangers and the like are mostly made of traditional alloy materials such as alloy steel, stainless steel, nickel-based corrosion-resistant alloy and the like, and a layer of compact oxide film/passive film is formed on the surface of the key structural parts, so that the alloy is protected from corrosion of aggressive ions (such as chloride ions in seawater). However, marine metal materials are subject to severe marine microbial corrosion (MIC) in addition to marine salt spray, seawater ionization, and chemical corrosion. In the marine environment, microorganisms form an uneven biofilm after attaching to the surface of the material, and the corrosion of metal components is accelerated through the metabolic activity of the microorganisms, so that the material fails. It is statistically calculated that material damage associated with marine microbial corrosion accounts for 70% to 80% of the total marine material. Therefore, the development of an alloy resistant to marine microbial corrosion is of great significance.

Disclosure of Invention

In view of the above, the invention provides a high-entropy alloy resistant to marine microbial corrosion, and a preparation method and application thereof.

In a first aspect, the invention provides a marine microorganism corrosion resistant high-entropy alloy, and the chemical general formula of the marine microorganism corrosion resistant high-entropy alloy is Al_0.1CoCrFeNiCu_xWherein x is the mole fraction of Cu, and x is more than or equal to 0.3 and less than or equal to 0.5.

In one embodiment of the present invention, in the chemical formula, x is in a range of 0.45 ≤ and 0.5 ≤. In another embodiment, x is in the range of 0.3 ≦ x ≦ 0.4. For example, x may be, but is not limited to, 0.3, or 0.32, or 0.35, or 0.38, or 0.4, or 0.42, or 0.45, or 0.48, or 0.5.

Further, optionally, the chemical general formula of the marine microorganism corrosion resistant high-entropy alloy is Al_0.1CoCrFeNiCu_0.5。

The marine microorganism corrosion resistant high-entropy alloy under the chemical general formula can obviously inhibit the growth of microorganisms on the surface of the alloy, and has excellent marine microorganism corrosion resistance.

Optionally, the crystal structure of the marine microorganism corrosion resistant high entropy alloy is a face centered cubic structure. The high-entropy alloy with the crystal structure and the marine microorganism corrosion resistance has high strength, high extension force and high toughness.

Optionally, the purity of Al, Co, Cr, Fe, Ni, and Cu in the marine microorganism corrosion resistant high entropy alloy is greater than 99.9%.

Optionally, the antibacterial rate of the high-entropy alloy resistant to marine microbial corrosion reaches over 90%. The marine microorganism corrosion resistant high-entropy alloy can effectively inhibit the corrosion of marine microorganisms, wherein the marine microorganisms can include but are not limited to pseudomonas aeruginosa.

Further, optionally, the antibacterial rate of the high-entropy alloy resistant to marine microbial corrosion reaches more than 95%.

In a second aspect, the invention also provides a preparation method of the high-entropy alloy resistant to marine microbial corrosion, which comprises the following steps:

(1) after surface pretreatment is carried out on metal elementary substance raw materials of Al, Co, Cr, Fe, Ni and Cu, adding the raw materials into smelting equipment according to the mole fraction ratio of 0.1:1:1:1: x, wherein x is more than or equal to 0.3 and less than or equal to 0.5;

(2) firstly melting the metal simple substance raw material into alloy liquid under inert atmosphere, cooling to obtain an alloy ingot, and turning the alloy ingot over for more than four times;

(3) and (3) repeating the step (2) at least twice, and after the metal simple substance raw material is uniformly smelted, forming by fixing a die to obtain the high-entropy alloy resistant to marine microbial corrosion.

Optionally, the metal elementary raw materials of Al, Co, Cr, Fe, Ni, and Cu are sequentially stacked and placed in the melting device in the order of the melting point from small to large. In one embodiment, Al and Cu are placed at the bottom, Co, Fe and Ni in the middle, and Cr at the top.

Optionally, the purity of the elementary metal raw materials of Al, Co, Cr, Fe, Ni, and Cu is greater than 99.9%.

Further, optionally, the purities of the elemental metal raw materials of Al, Co, Cr, Fe, Ni, and Cu are all greater than 99.99%.

Optionally, the surface pretreatment process comprises: and removing oxide skins on the surfaces of the metal elementary substance raw materials of Al, Co, Cr, Fe, Ni and Cu, and then carrying out ultrasonic cleaning and drying. Wherein, the ultrasonic cleaning process can be but is not limited to be carried out in absolute ethyl alcohol.

Optionally, the smelting apparatus is a non-consumable vacuum arc furnace; before the smelting equipment is used for smelting the high-entropy alloy resistant to marine microorganism corrosion, metal titanium is smelted to remove impurities in the smelting equipment. By smelting the metallic titanium firstly, impurities such as free oxygen, nitrogen and the like in the smelting equipment can be effectively absorbed.

Optionally, the inert atmosphere in step (2) may be achieved by subjecting the smelting plant to at least one evacuation process. Each vacuumizing process comprises vacuumizing the smelting equipment, and then introducing inert gas; wherein the inert gas comprises argon.

In one embodiment of the invention, the smelting equipment is vacuumized, and when the vacuum degree reaches 5 multiplied by 10^-3After Pa, filling argon gas with about half atmospheric pressure into the smelting equipment; the process is then repeated once more so that the melting process is carried out under an inert atmosphere such as argon.

Optionally, in the step (2), after the elemental metal raw material is melted into an alloy liquid, the alloy liquid is stirred at a constant temperature. For example, when melting is performed by using a non-consumable vacuum arc furnace, the arc current is adjusted to heat and melt the elemental metal raw material to form an alloy liquid, then the arc holding time is 60-120s, and cooling is performed to obtain an alloy ingot. Through the constant-temperature stirring process, the metal simple substance raw materials can be well and uniformly mixed.

In the present invention, in the step (2), the melting temperature may be, but is not limited to, higher than 400-. Alternatively, the melting temperature may be, but is not limited to, 2000-.

Optionally, in the step (3), in the fixed die forming process, the alloy obtained by uniformly smelting the elemental metal raw material may be suction cast into a mold for forming through vacuum suction casting equipment. Through the vacuum suction casting equipment, the alloy is effectively prevented from being polluted by impurities in the cooling and forming process.

Alternatively, the alloy may be suction cast into molds of different sizes or shapes depending on the size and shape of the desired product. Optionally. The mold may be, but is not limited to, a water-cooled copper mold.

Optionally, the crystal structure of the marine microorganism corrosion resistant high entropy alloy is a face centered cubic structure.

In one embodiment of the invention, the alloy is suction cast into a water-cooled copper mold to obtain a high-entropy alloy cylindrical sample with the diameter (phi) of 10mm and marine microorganism corrosion resistance.

In a third aspect, the invention also provides an application of the high-entropy alloy resisting marine microbial corrosion in the first aspect of the invention or the high-entropy alloy resisting marine microbial corrosion prepared by the preparation method in the second aspect of the invention in marine engineering equipment. In an embodiment, the high entropy alloy that is resistant to marine microbial corrosion may be used, but is not limited to, components for direct contact with seawater. Because the high-entropy alloy resistant to marine microorganism corrosion has strong marine microorganism corrosion resistance, when the high-entropy alloy is used for parts such as equipment shells, equipment can be effectively protected, and the service life of the equipment is prolonged.

Alternatively, the marine engineering equipment may include, but is not limited to, seawater piping, pump valves, heat exchangers, or racks. The ocean engineering equipment can also be other ocean underwater equipment.

The beneficial effects of the invention comprise the following aspects:

(1) the high-entropy alloy resistant to marine microbial corrosion is a hexahydric alloy containing Al, Co, Cr, Fe, Ni and Cu, and the chemical general formula of the high-entropy alloy is Al_0.1CoCrFeNiCu_xWherein x is more than or equal to 0.3 and less than or equal to 0.5, and the crystal structure is a face centerThe high-entropy alloy material has a cubic structure, maintains good corrosion resistance of the material, and has excellent marine microorganism corrosion resistance.

(2) The preparation method of the marine microorganism corrosion resistant high-entropy alloy has simple process, is easy to realize industrial production, and the prepared high-entropy alloy material has excellent marine microorganism corrosion resistance due to uniform mixing of all metal simple substance raw materials; meanwhile, the high-entropy alloy resistant to marine microbial corrosion is obtained by smelting common pure metal simple substance raw materials, is low in preparation cost, can protect equipment from corrosion in a marine environment, and has a good application prospect in marine engineering structural components.

Advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of embodiments of the invention.

Drawings

In order to more clearly illustrate the contents of the present invention, a detailed description thereof will be given below with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a process flow diagram of a method for preparing a high-entropy alloy resistant to marine microbial corrosion according to an embodiment of the invention;

FIG. 2 is a material characterization diagram of a high-entropy alloy resistant to marine microbial corrosion according to an embodiment of the present invention, wherein (a) in FIG. 2 is an X-ray diffraction pattern; FIG. 2 (b) is a secondary electron microscopic image.

FIG. 3 is a graph showing the results of plating of various alloys with P.aeruginosa for 24 hours according to one embodiment of the present invention; wherein (a) in FIG. 3 is 316L stainless steel, (b) in FIG. 3 is Al-Co-Cr-Fe-Ni high-entropy alloy, (c) in FIG. 3 is high-entropy alloy resistant to marine microorganism corrosion, and (d) in FIG. 3 is antibacterial ratio histogram;

fig. 4 is an electrochemical potentiodynamic polarization curve of the high-entropy alloy resisting marine microbial corrosion and 316L stainless steel provided by the embodiment of the invention.

Detailed Description

While the following is a description of the preferred embodiments of the present invention, it should be noted that those skilled in the art can make various modifications and improvements without departing from the principle of the embodiments of the present invention, and such modifications and improvements are considered to be within the scope of the embodiments of the present invention.

The following examples are intended to illustrate the invention in more detail. The embodiments of the present invention are not limited to the following specific embodiments. The present invention can be modified and implemented as appropriate within the scope of the main claim.

Unless otherwise specified, the raw materials and other chemicals used in the examples of the present invention are commercially available.

Referring to fig. 1, an embodiment of the present invention provides a method for preparing a high-entropy alloy resistant to marine microbial corrosion, including:

s10, after surface pretreatment is carried out on metal elementary substance raw materials of Al, Co, Cr, Fe, Ni and Cu, adding the raw materials into smelting equipment according to the mole fraction ratio of 0.1:1:1:1: x, wherein x is more than or equal to 0.3 and less than or equal to 0.5;

s20, melting the metal simple substance raw material into an alloy liquid under an inert atmosphere, cooling to obtain an alloy ingot, and turning the alloy ingot over more than four times;

and S30, repeating the step S20 at least twice, and after the metal simple substance raw material is uniformly smelted, forming in a fixed die to obtain the high-entropy alloy resistant to marine microorganism corrosion.

Wherein, in the step S10, the surface pretreatment process includes: and removing oxide skins on the surfaces of the metal elementary substance raw materials of Al, Co, Cr, Fe, Ni and Cu, and then carrying out ultrasonic cleaning and drying. Wherein, the surface scale of the elemental metal raw material can be removed by but not limited to using sand paper or a grinder. Alternatively, the ultrasonic cleaning process may be performed in, but not limited to, absolute ethanol.

Optionally, the smelting apparatus is a non-consumable vacuum arc furnace; before the smelting equipment is used for smelting the high-entropy alloy resistant to marine microorganism corrosion, metal titanium is smelted to remove impurities in the smelting equipment. By smelting the metallic titanium firstly, impurities such as free oxygen, nitrogen and the like in the smelting equipment can be effectively absorbed.

In step S20, the inert atmosphere may be realized by performing at least one vacuum process on the smelting device. Each vacuumizing process comprises vacuumizing the smelting equipment, and then introducing inert gas; wherein the inert gas comprises argon.

In one embodiment of the invention, the smelting equipment is vacuumized, and when the vacuum degree reaches 5 multiplied by 10^-3After Pa, filling argon gas with about half atmospheric pressure into the smelting equipment; the process is then repeated once more so that the melting process is carried out under an inert atmosphere such as argon.

In the step S20, after the elemental metal raw material is melted into an alloy liquid, the alloy liquid is stirred at a constant temperature. For example, when melting is performed by using a non-consumable vacuum arc furnace, the arc current is adjusted to heat and melt the elemental metal raw material to form an alloy liquid, then the arc holding time is 60-120s, and cooling is performed to obtain an alloy ingot. Through the constant-temperature stirring process, the metal simple substance raw materials can be well and uniformly mixed.

In the step S20, the melting temperature may be, but is not limited to, higher than 400-. Alternatively, the melting temperature may be, but is not limited to, 2000-.

In the step S30, in the fixed die forming process, the alloy obtained by uniformly smelting the metal simple substance raw material may be suction cast into a die by a vacuum suction casting device for forming. Through the vacuum suction casting equipment, the alloy is effectively prevented from being polluted by impurities in the cooling and forming process. For example, the high entropy alloy reacts with oxygen or nitrogen in the air, etc.

Alternatively, the alloy may be suction cast into molds of different sizes or shapes depending on the size and shape of the desired product. Optionally. The mold may be, but is not limited to, a water-cooled copper mold.

The crystal structure of the marine microorganism corrosion resistant high-entropy alloy prepared by the preparation method provided by the embodiment of the invention is a face-centered cubic structure.

The following examples are intended to illustrate the invention in more detail.